Building block

ABSTRACT

A block has a finished surface that provides an attractive appearance. The block is relatively large in size, allowing the quick construction of a wall, such as a retaining wall, using the block. The block includes one or more lift devices embedded in the block that allow the block to be lifted using a suitable lifting apparatus, such as a crane, forklift, backhoe, etc. The block includes multiple retaining knobs that protrude from the lower surface of the block and help to align a block with previously-laid blocks underneath.  
     The block includes multiple voids that extend from the top surface to the bottom surface of the block, and that align with each other when the blocks are stacked into a wall, thereby allowing fill material to be placed in the voids to strengthen the wall. The block is constructed using a block forming apparatus that includes one or more form panels that each have multiple form liners to provide a textured surface of the block. Each form panel may be pivoted away from a bottom surface of the block forming apparatus for easy removal of the block and for easy changing of the panels to fabricate blocks with different characteristics using the same block forming apparatus. The preferred embodiments also include methods for doing business, including the selling, leasing, and purchasing of the block forming apparatus for on-site fabrication of blocks.

BACKGROUND OF THE INVENTION

[0001] 1. Technical Field

[0002] This invention generally relates to construction materials and techniques, and more specifically relates to a building block, a method for making the block, a method for building a wall using the block, and methods for doing business using a block forming apparatus to fabricate the block.

[0003] 2. Background Art

[0004] Building blocks have been used for centuries to construct homes, office buildings, churches, and many other structures. Early building blocks were hewn from stone into appropriate shapes that were assembled together, typically using mortar, to form a wall. In modem times, various types of concrete blocks have been developed, which are typically formed by pouring a cement mixture into a form and allowing the cement to cure. This type of cement block is strong and makes for a sturdy wall, but installing a traditional concrete block requires a skilled mason that must manually lift each block, and set each block using mortar to secure the blocks in place. This process is very labor-intensive.

[0005] One application for concrete blocks is the construction of retaining walls. Retaining walls are required when there is a body of earth that needs to be held in place. While several different block designs have been used in the art, most of these are relatively small blocks that a construction worker must manually lift and put in place. Most require mortar. What is needed is a large block that is especially well-suited for retaining walls that has a large surface, and that may be lifted into place using a crane or other suitable equipment, and that may be stacked into a wall without mortar. This allows a wall to be quickly and efficiently constructed using much less skilled labor. It would also be desirable for the block to have an attractive, finished look that does not require covering or painting, but that also could be stained to look like many different types of rocks or stones or to match a desired color scheme.

DISCLOSURE OF INVENTION

[0006] According to the preferred embodiments, a block has a finished surface that provides an attractive appearance. The block is relatively large in size, allowing the quick construction of a wall, such as a retaining wall, using the block. The block includes one or more lift devices embedded in the block that allow the block to be lifted using a suitable lifting apparatus, such as a crane, forklift, backhoe, etc. The block includes multiple retaining knobs that protrude from the lower surface of the block and help to align a block with previously-laid blocks underneath. The block includes multiple voids that extend from the top surface to the bottom surface of the block, and that align with each other when the blocks are stacked into a wall, thereby allowing fill material to be placed in the voids to strengthen the wall. The block is constructed using a block forming apparatus that includes one or more form panels that each have multiple form liners to provide a textured surface of the block. Each form panel may be pivoted away from a bottom surface of the block forming apparatus for easy removal of the block and for easy changing of the panels to fabricate blocks with different characteristics using the same block forming apparatus. The preferred embodiments also include methods for doing business, including the selling, leasing, and purchasing of the block forming apparatus for on-site fabrication of blocks.

[0007] The foregoing and other features and advantages of the invention will be apparent from the following more particular description of preferred embodiments of the invention, as illustrated in the accompanying drawings.

BRIEF DESCRIPTION OF DRAWINGS

[0008] The preferred embodiments of the present invention will hereinafter be described in conjunction with the appended drawings, where like designations denote like elements, and:

[0009]FIG. 1 is a top view of a first implementation of a block in accordance with the preferred embodiments;

[0010]FIG. 2 is front view of the block of FIG. 1 taken along the lines 2-2;

[0011]FIG. 3 is a side view of the block of FIGS. 1 and 2 taken along the lines 3-3 in FIG. 2;

[0012]FIG. 4 is a side view of an alternative implementation for the block of FIG. 2;

[0013]FIG. 5 is an enlarged detail view of the lifting device 170 shown in FIG. 3 in accordance with the preferred embodiments;

[0014]FIG. 6 is a side view of the lifting device in FIG. 5 taken along the lines 6-6;

[0015]FIG. 7 is top view of a second implementation of a block in accordance with the preferred embodiments showing the side walls tapering the opposite direction when compared to the side walls of the block in FIG. 1;

[0016]FIG. 8 is side view of blocks being stacked together to form a retaining wall in accordance with the preferred embodiments;

[0017]FIG. 9 is a top view of a retaining wall that could be constructed using the block shown in FIG. 1;

[0018]FIG. 10 is a top view of a retaining wall that could be constructed using the block shown in FIG. 7;

[0019]FIG. 11 is top view of a block forming apparatus in accordance with the preferred embodiments;

[0020]FIG. 12 is a cross-sectional side view of the block forming apparatus of FIG. 11 taken along the lines 12-12;

[0021]FIG. 13 is a front view of the block forming apparatus of FIG. 11 taken along the lines 13-13;

[0022]FIG. 14 is an inside view of the front form panel 1110 shown in FIGS. 11-13;

[0023]FIG. 15 is a cross-sectional side view of the form shown in FIG. 14;

[0024]FIG. 16 is a first implementation of the circled portion 1530 of FIG. 15 in accordance with the preferred embodiments that uses multiple form liners;

[0025]FIG. 17 is a second implementation of the circled portion 1530 of FIG. 15 in accordance with the preferred embodiments that uses a metal frame that defines form pockets, with a form liner within each form pocket;

[0026]FIG. 18 is a perspective view of the form of FIGS. 14, 15 and 17;

[0027]FIG. 19 is a flow diagram of a method for fabricating a block in accordance with the preferred embodiments;

[0028]FIG. 20 is a flow diagram of a method that may be performed while preparing the form in step 1910 of FIG. 19;

[0029]FIG. 21 is a flow diagram of a method that may be performed while preparing the form in step 1910 of FIG. 19;

[0030]FIG. 22 is a flow diagram of a method for constructing a wall using the block of the preferred embodiments; and

[0031] FIGS. 23-26 are flow diagrams of methods for doing business in accordance with the preferred embodiments.

BEST MODE FOR CARRYING OUT THE INVENTION

[0032] Referring now to FIGS. 1-3, a building block 100 in accordance with the preferred embodiment includes a front surface 110, a left side surface 120, a right side surface 130, and a back surface 140, all coupled together via top surface 150 and bottom surface 160. In the preferred embodiments, any or all of the front surface 150 and the side surfaces 120 and 130 could have a finished, decorative surface. In the specific embodiment shown in FIGS. 1-3, we assume that front surface 110 has a decorative surface as shown in FIG. 2. From surface 110 has the appearance of stone that has been stacked together using mortar joints. Each rectangular panel 210, 211, 212, 213, and 214 represent a stone, while the lines between the panels 220, 221, 222 and 223 represent mortar joints between the stones. Each panel 210-214 preferably has a textured finish that gives the panels a stone-like appearance. Note, however, that any suitable finish may be used for any of the front surface 110 and side surfaces 120 and 130, and that the block material may be colored and the finished surface may be stained or painted to achieve a desired look. The preferred embodiments expressly extend to any type of finished surface on block 100.

[0033] Referring to FIG. 3, for the specific configuration shown in the drawings, the front surface 110 has an uneven surface comprised of a lower portion 314 and an offset upper portion 312. The offset upper portion 312 gives the appearance of a separate course of stone than the lower portion 314, and enhances the look of a finished wall that is built using the block 100.

[0034] Block 100 includes a plurality of voids (e.g., 182, 184, 186 and 188 in FIG. 1) that extend from the top surface 150 to the bottom surface 160. These voids are designed to align with the voids of other blocks when the blocks are stacked to form a wall. Once a wall is formed, the voids may be filled with an appropriate filler material, such as recycled concrete, gravel, concrete, etc.

[0035] Back surface 140 has a sloped surface that slopes from the top surface 150 to the bottom surface 160, as shown best in FIG. 3. Block 100 also includes one or more retaining knobs 230 that provide a mechanism for easily positioning one block atop another previously-placed block. Block 100 also includes lifting devices 170 (FIG. 1) that are embedded in the block that allow easily lifting the block using any appropriate means of lifting, such as a crane, forklift, backhoe, etc.

[0036] Block 100 is preferably comprised of a mixture of sand, gravel, cement, and water. The cement is preferably Portland cement, type 1, ASTM designation C150 or similar. The resulting mix is preferably denoted SG3000 (sand-gravel-3000), which represents a mixture of sand, gravel, cement, and water in proportions that results in a finished product capable of bearing approximately 3000 pounds per square inch (209 kilograms per square centimeter). Note that SG3000 is a common expression in the concrete art that denotes specific proportions of the ingredients. While SG3000 is the preferred block material, the preferred embodiments also extends to any other suitable block material that may be formed as disclosed herein.

[0037] Referring now to FIG. 3, a lifting device 170 is embedded into the block material. An enlarged section 310 of FIG. 3 is shown in more detail in FIG. 5. Lifting device 170 comprises a cup member 520 with a slit through which one end of an anchor member 530 protrudes (as shown by the dotted portion of 530 in FIG. 5 that extends up into the cup portion 520). As shown in FIG. 6, anchor member 530 includes a plurality of holes (e.g., 532, 534 and 536). The top hole 532 is within the cup portion 520, which allows a hook or other anchor to be placed through the hole 532 to life the block 100. A piece of rebar 540 is preferably placed through a hole 536 in the anchor member to securely anchor the lifting device 170 to the block by embedding the lifting device 170 and rebar 540 into the block material when the block is being formed. Note that the details of lifting device 170 as shown in FIGS. 3, 5 and 6 are shown as one suitable way to provide a lifting device 170 within the block 100. Of course, other variations are also possible within the scope of the preferred embodiments. For example, rebar could also be passed through hole 534 to more securely anchor the lifting device 170 within the block. The preferred embodiments expressly extend to any suitable configuration for a lifting device 170 or a number of different lifting devices 170 that are capable of supporting the weight of the block 100, thereby allowing a suitable means for lifting the block to install the block in a wall.

[0038]FIG. 4 shows an alternative side view for block 100 that has an L-shape rather than the shape shown in FIG. 3. This L-shaped block could be used as a top block, with gravel, dirt, or concrete placed as fill material (shown as 420 in FIG. 4) to hold the top block in place and to provide a finished top surface for a retaining wall built using the block 100. This block could also be used to provide a finished shore line for a lake or pond. Note that in this L-shaped block, the back surface 140 could have a finished decorative surface in addition to the front surface 110, thereby providing an attractive way to top off a retaining wall. Furthermore, the block of FIG. 4 could be provided without voids 182, 184, 186 and 188 in FIG. 1, eliminating the need of filling the voids before the wall may be finished.

[0039] In the preferred embodiments, the side surfaces 120 and 130 may taper from the front surface 110 to the back surface 140, as shown in FIG. 1. This configuration allows the blocks to be stacked in a straight wall, which would leave triangular voids between the side surface 120 of one block and the opposing side surface 130 of the adjacent block. In the alternative, the triangular void between blocks may be reduced or eliminated to provide an outside curve in the wall. To achieve the tightest curve possible, the side portion 120 of one block may be butted up flush with the opposing side portion 130 of the adjacent block, leaving no void between side portions. This is shown in FIG. 9, where the blocks are stacked in an outside curve to retain material 920. Note that another course of blocks is shown in phantom in FIG. 9 to illustrate that the voids in the blocks line up, even in a curved wall.

[0040] Another variation within the scope of the preferred embodiments has a taper that extends from the back surface 140 to the front surface 110, as shown in FIG. 7. This configuration allows the creation of an inside curve to retain material 920, as shown in FIG. 10. Again in FIG. 10, another course of blocks is shown in phantom to illustrate the alignment of the voids. Of course, it is also within the scope of the preferred embodiments to provide sides that are not tapered, i.e., that are at a right angle to both the front surface 110 and the back surface 140. The preferred embodiments also anticipate any combination of straight and tapered side portions in a single block, and any combination of blocks according to the particular wall being built.

[0041] Note that the configuration shown in FIG. 7 also includes a drain tile 710 integrally formed within the block, which is also shown in phantom in block 100A of FIG. 8. Retaining walls often require some type of drainage system to prevent the static pressure of water build-up behind the wall. Including a drain tile 710 within block 100 allows a drainage system to be easily constructed without cutting notches in the block 100. Note that drain tile 710 is preferably incorporated into the blocks that make up a base course, but would likely not be needed in any other course in most applications. Note also that drain tile 710 may extend from the back surface 140 to the front surface 110, as shown in FIG. 7. In the alternative, drain tile 710 could extend from the back surface 140 to just short of the front surface 110, such that the portion of front surface 110 covering the drain tile could be easily broken away with a hammer to expose the drain tile 710. By hiding the drain tile 710 behind a thin portion of front surface 110, the drain tile could be present yet hidden if not used.

[0042] As stated above, the retaining knobs 230 aid in positioning the blocks as they are stacked to form a retaining wall. This is shown in FIG. 8. A base block 100A is first positioned in place. Note that in the preferred embodiment illustrated in FIG. 8, the base block 100C does not include any retaining knobs 230, to facilitate laying the block flat on the ground or other surface 830 on which the wall is to be built. However, it is equally within the scope of the preferred embodiments to use a block with retaining knobs 230 as a base block, which would require that the surface 830 be prepared with sand or gravel that would be displaced as the base block is positioned in place. Once the base block 100A is in place, the next block 100B can be positioned atop the base block 110A, as shown in FIG. 8, using the retaining knobs as a guide. This guiding function of the retaining knobs 230 is shown by block 100C, which is stacked atop block 100B. In the preferred embodiments, the retaining knobs 230 have a tapered surface 810 that is intended to meet a top portion 820 of the back surface of the block below. Thus, block 100C is lifted above block 100B, and its position is changed until the front tapered portion 810 of the retaining knob 230 is above the top portion 820 of the block below. The block 110C is then lowered into place, with the front surface 810 of the retainer knob preferably rubbing along the top portion 820 of the block below until the block 100C is seated into place. Block 100B is seated into place atop block 100A, as shown. The result is that each block is held by retaining knobs 230 to one or more blocks below, thereby interlocking the blocks to increase the strength of the wall.

[0043] The preferred embodiments include a block forming apparatus. One suitable implementation of a block forming apparatus is shown in FIGS. 11-18. Referring now to FIGS. 11-13, a block forming apparatus 1100 is used to form the block 100 shown in FIGS. 1-3. Block forming apparatus 1100 includes a front form panel 1110, a left side form panel 1120, a right side form panel 1130, and a back form panel 1140 that are all pivotally coupled to a bottom form panel 1190 so that each of the front, side, and back form panels may pivot away from a block to facilitate removal of the block from the block forming apparatus 1100. Left side form panel 1120 may include a triangular portion 1122 that creates the tapered side panel 120 in FIG. 1. Similarly, right side form panel 1130 may include a triangular portion 1132 that creates the tapered side panel 130 in FIG. 1. Multiple void forms 1182, 1184, 1186 and 1188 are attached to the bottom form panel 1190 and extend upward to the top of the apparatus 1120, as shown best in FIG. 12, to create the respective voids 182, 184, 186 and 188 in the block of FIG. 1. Note that the void forms are preferably tapered, as shown in FIG. 12, to facilitate the removal of the block from the block forming apparatus. The bottom form panel 1190 also includes pockets 1150 that will create the retaining knobs 230 on block 100.

[0044]FIG. 12 shows a cross-sectional side view of the block forming apparatus of FIG. 11 along the line 12-12. Back form panel 1140 extends beyond vertical to create the tapered back surface 140 of the block of FIG. 1. In the preferred embodiments the angle of taper of the back surface is preferably between five and twenty-five degrees, with the preferred taper being fifteen degrees. Front form panel 1110 includes a form that will create an attractive, finished surface on the front surface 110 of the block 100, as discussed in more detail below. One suitable finished surface for block 100 is shown in FIG. 2, with each panel 210-214 having a textured surface to resemble natural stone. Note that the back and front form panels 1110 and 1140 pivot away from the block, as shown in phantom in FIG. 12, to facilitate the removal of the block 100 from the block forming apparatus 1100.

[0045]FIG. 13 is a front view of the block forming apparatus 1100 of FIG. 11 taken along the line 13-13. The left side form panel 1120 and right side panel 1130 are shown abutting the front form panel 1110. Note that the front form panel 1110 preferably includes multiple reinforcing ribs 1310 to give the front form panel 1110 the required strength. Some of the reinforcing ribs 1310 are pivotally coupled to the bottom form panel 1190 in a way that allows the front form panel 1110 to pivot away, as shown in phantom in FIG. 12. These reinforcing ribs preferably have the same configuration as the portions shown on left side form panel 1120 and right side form panel 1130 shown in FIG. 13. Note the pockets 1150 in FIG. 13 that will form the retaining knobs 230 on block 100. Also note that the left side form panel 1120 and right side form panel 1130 may pivot away from the vertical position, similar to the phantom view of front form panel 1110 in FIG. 12.

[0046] Block forming apparatus 1100 includes fork lift pockets 1320 and 1330 running through the bottom form panel 1190. These fork lift pockets 1310 and 1320 allow the block forming apparatus 1110 to be easily loaded by a forklift onto a truck for transporting the block forming apparatus to a remote location. As discussed in more detail below, the ability to fabricate blocks on-site is a tremendous advantage of the present invention.

[0047] The side of the front form panel 1110 shown in FIGS. 11-13 that creates the textured front surface 110 of the block 100 is shown in FIG. 14. Note that there are dividers 1420, 1421, 1422, and 1423 that create the respective dividing lines 220, 221, 222 and 223 on the front surface 110 of block 100 shown in FIG. 2. FIG. 15 is a cross-sectional side view of the front form panel 1110 of FIG. 14 taken along the line 15-15. As shown in FIG. 15, the surface of the front form panel 1110 that faces the block has an upper portion 1510 that extends further toward the block than the lower portion 1520, as shown in the circled portion 1530 of FIG. 15. There are several ways to accomplish the offset faces, as shown by way of example in FIGS. 16 and 17.

[0048] One way to achieve the set-back upper portion of the block (as shown by 312 and 314 in FIG. 13) is to provide multiple polyurethane form liners that are attached to a flat plate or board. One example of this configuration is shown in FIG. 16, where an upper form liner 1610 and a lower form liner 1620 are attached to a flat plate 1630. Note that upper form liner 1610 is thicker than lower form liner 1620, thereby creating the desired offset between the bottom half of the block and the top half of the block. The configuration of FIG. 16 would work with one form liner for the bottom half 1520 and a separate form liner for the top half 1510. This configuration would also work with one form liner for each panel that is defined on the front surface 110 of the block. For the example of FIG. 14, this would mean separate form liners for each of panels 1410-1414. The preferred embodiments use separate form liners for each of panels 1410-1414. This allows one form liner to be easily replaced if damaged without requiring replacement of other portions that are undamaged.

[0049] Another embodiment of the front form panel is shown in FIG. 17. Two pieces of angled metal 1740 and 1750 are attached to a flat backing plate 1730. A form pocket liner 1720 is then placed in the form pocket created by the angled metal 1750. A spacer block 1760 is placed within the form pocket created by the angled metal 1740, and another form pocket liner 1710 is placed within the form pocket on top of the spacer block 1760. For the preferred embodiments as shown in FIG. 3, the upper face 312 of the block is set back 1.5 inches (3.8 cm) from the lower face 314. For a 1.5 inch (3.8 cm) setback, the spacer block 1760 of FIG. 17 could be any 2× lumber (such as 2×4s) that has a nominal thickness of 1.5 inches.

[0050] One advantage of the configuration of FIG. 17 is that the metal frame defined by the angle metal 1740 and 1750 is the portion of the front form panel 1110 that is most deeply embedded into the block, and therefore has the greatest wear and tear when removing the front form panel 1110 from the block after curing. By making the frame portion out of metal, the form is very durable. In addition, by using individual form liners (e.g., 1710 and 1720 in FIG. 17) in each pocket defined by the metal frame, a form liner that becomes damaged may be individually replaced. If the entire front form panel were covered with a single form liner, as is common in the art, any damage of any portion of the single form liner would necessitate the expense of replacing the entire single form liner. In addition, a large form liner is more expensive to produce than several smaller form liners. For these reasons, a significant advantage of the block forming apparatus of the preferred embodiments is the presence of a plurality of form liners that may be each be individually replaced when needed without replacing any of the other form liners.

[0051] The preferred material for the form liners is polyurethane rubber. Note, however, that many other materials could be used within the scope of the preferred embodiments. Molded plastic would work well, and would allow a wide variety of textures to be placed on a surface of a block. Stacked sheets of cut steel could also be used to create a layered effect. Hammered copper could be used to create a desired textured finish. The preferred embodiments expressly extend to any and all materials that may be suitable for use as a form liner.

[0052]FIG. 18 shows a perspective view of the front form panel 1110 shown in FIGS. 14, 15 and 17 without showing the form pocket liners 1710 and 1720. This is a view of the embodiment of FIG. 17 that uses a metal frame. The portions of the metal frame 1820, 1821, 1822, and 1823 create the dividing joints 1420, 1421, 1422, and 1423 in FIG. 14. Similarly, the individual form pockets 1810, 1811, 1812, 1813, and 1814 create the respective panels 1410, 1411, 1412, 1413, and 1414 in FIG. 14. Note that form pockets 1410 and 1412 have no side piece because they represent half-blocks, which will appear as full blocks when abutted next to an adjacent block. Also note that metal frame portions 1424 and 1425 are half the thickness of the other metal frame portions 1420-1423, so that abutting two blocks next to each other will result in a thickness of a joint that is the same as the other joints between panels. By placing individual form liners in each of the form liner pockets 1810-1814, each form liner may be individually replaced independent of the other form liners. The combination of the metal frame and individual form liners provides advantages not know in the art. It is also within the scope of the preferred embodiments to provide no form liners within the form pockets 1810-1814, which results in a smooth, flat face on the block, with the appearance of joints between the panels defined by the front form panel.

[0053] The preferred embodiments extend to various methods for fabricating a block, for building a wall using a block, and for doing business using the block forming apparatus discussed above. Referring now to FIG. 19, a method 1900 is a method for forming a block using the block forming apparatus of FIGS. 11-13. The first step is to prepare the block forming apparatus (step 1910). Preparing the block forming apparatus entails the steps of placing the front form panel, left and right side form panels, and back form panel in their respective positions in preparation for pouring a block. This step includes attaching the side panels to the front panel and to the back panel to create a rigid, box-like structure into which a block material may be poured or otherwise formed. Another step in preparing the form is to cover the void forms 1182-1188 with a material to facilitate removal of the block from the form. Suitable materials include canvas, tarp, rubber, kevlar, vinyl, etc. Another step in preparing the form is to spray all surfaces of the form that will contact the block material with a release agent, such as form oil.

[0054] Once the form is prepared in step 1910, the block material may be mixed (step 1920). As stated above, the preferred block material is SG3000 concrete. However, any other suitable block material may be used within the scope of the preferred embodiments, including materials that are not concrete-based. Once mixed, the block material is poured into the block forming apparatus (step 1930). The block material is then vibrated to eliminate voids and air pockets (step 1940). The preferred method of vibrating is to use a hand-held vibrator that is pushed into the block material at various locations along the form. However, it is equally within the scope of the preferred embodiments to mount vibrators on the form panels themselves, thereby achieving a high-quality surface without voids and air pockets, or to mount a single vibrator, such as an air vibrator, on the bottom form panel. If the form is not full (step 1950=NO), rebar is added on top of the block material (step 1960), and steps 1930, 1940 and 1950 are repeated. In the preferred embodiments, the form is filled approximately one-third full, rebar is placed on top of the block material, the form is then filled to approximately two-thirds full, rebar is again placed on top of the block material, and the form is then filled the rest of the way. Once the form is full (step 1950=YES), the block material is leveled to the desired height (step 1970). One or more lifting devices are then installed (step 1972), preferably by pushing the lifting device and rebar (shown in FIGS. 5 and 6) into the block material until the top of the cup portion 520 is level with the top of the block material. The block is then allowed to cure (step 1980). Once the block has cured, the form panels are opened (i.e., pivoted away from the block), and the block is then removed from the form (step 1990). The easiest way to remove the block from the form is to hook onto the lifting devices 170 and lift the block using a crane, backhoe, etc. The block is now ready to be stacked into a wall.

[0055] One significant advantage of the preferred embodiments is the ability to quickly and easily change the configuration of the block forming apparatus to make different blocks. Note that each of the four doors that define the front, two side, and back form panels are separate from each other. This means that any of these panels may be replaced independently from the other panels. If a finished look is needed on both the front surface and the left side surface, form panels with the form liners could be installed for both the front form panel and the left side form panel. If the sides need to be tapered one direction, side panels with triangular portions may be used, as shown in FIG. 11. If the sides need to be tapered in the opposite direction, the side panels of FIG. 11 could be swapped. If the sides don't need to be tapered, the side panels could be flat. The block forming apparatus of the preferred embodiments thus provides great flexibility by allowing many different types of blocks to be formed by simply changing out form panels according to the desired configuration of the block. This flexibility is shown by methods 2000 and 2100 in FIGS. 20 and 21. In method 2000 of FIG. 20, for each block face that requires a finished surface, a form panel is used that has multiple form liners (step 2010). This step corresponds to the configuration shown in FIG. 16, where multiple form liners 1610 and 1620 are used to achieve the desired finished surface. For each block face that does not require a finishes surface, a flat form panel is used (step 2020).

[0056] In method 2100 of FIG. 21, for each block face that requires a finished surface, a form panel is used that include multiple form pockets, with each form pocket having an individual form liner. This step corresponds to the configuration shown in FIG. 17, where multiple form liners 1710 and 1720 are placed within form pockets. For each block that does not require a finished surface, a flat form panel is used (step 2120). Note that methods 2000 and 2100 would be suitably performed during the preparation of the form in step 1910 of FIG. 19.

[0057] Referring to FIG. 22, a method 2200 for building a retaining wall using the block of the preferred embodiments begins by lifting and placing each block in place next to other blocks to form a first course (step 2210). Note that in the preferred embodiments, the base blocks used to form the first course preferably do not have retainer knobs, as shown by block 100A in FIG. 8, and may include a drain tile 710. For the second and each subsequent course, each block is lifted and placed using its retainer knobs to align the block being placed with the block or blocks below it (step 2220), as shown in FIG. 8. In the preferred embodiments, the blocks are preferably stacked using a running bond, where a block above spans half of two blocks underneath, to provide a strong, interlocked wall. Next, the voids may be filled with an appropriate filler material (step 2230), such as sand, gravel, recycled concrete, etc. Note also that the voids may be filled with rebar and poured concrete to form a very strong wall. The step 2230 of filling the voids is an optional step, and may not be required in many instances, depending on the configuration of the wall being built and its anticipated load.

[0058] Various methods of doing business also arise from the unique block forming apparatus discussed above. One of the significant benefits of the block forming apparatus is the ability to transport the block forming apparatus to a job site and construct blocks on-site. This could result in a huge savings in shipping costs. Needless to say, large concrete blocks are heavy, and thus incur a significant expense in transporting the blocks to a job site. If the blocks may be fabricated on-site using equipment (such as cement trucks and cranes) that is present on-site, and using materials (such as gravel, cement, and sand) that is present on-site, the savings in shipping costs may be significant. For this reason, the methods for doing business disclosed herein center around the concept of using the block forming apparatus to construct blocks on-site. Note that the methods for doing business that are disclosed herein relate to methods for doing business with the block forming apparatus of the present invention.

[0059] Referring to FIG. 23, one method 2300 for doing business within the scope of the preferred embodiments is to fabricate the block forming apparatus (step 2310), then sell the block forming apparatus for on-site block fabrication (step 2320). While concrete forms are known that can be sold and then used to pour walls on-site, method 2300 references the specific block forming apparatus of the present invention, and sells the block forming apparatus to be used for fabricating blocks on a construction site. Because the prior art does not disclose any block forming apparatus for forming blocks on a construction site, method 2300 of doing business is an advance in the art.

[0060] Another method 2400 for doing business within the scope of the preferred embodiments is shown in FIG. 24. First, the block forming apparatus is fabricated (step 2410). Next, the block forming apparatus is leased for on-site block fabrication (step 2420). By leasing the block forming apparatus, the potential profit margin is even greater than a sale, because the block forming apparatus will be returned after the lease period and will be available for someone else to lease it.

[0061] Yet another method 2500 for doing business within the scope of the preferred embodiments is shown in FIG. 25. First, the block forming apparatus is purchased (step 2510). Next, the block forming apparatus is sold or leased for on-site block fabrication (step 2520). Method 2500 is thus a way for a middle-man (such as a company that sells or rents construction equipment) to profit from the block forming apparatus of the present invention.

[0062] Still another method 2600 for doing business within the scope of the preferred embodiments is shown in FIG. 26. First, the block forming apparatus is purchased (step 2610). Next, the block forming apparatus is used for on-site block fabrication (step 620). Method 2600 is thus a way for a construction company to do business by using the block forming apparatus of the present invention to fabricate blocks on-site.

[0063] Note that the drawings herein do not show any dimensions for the block or the block forming apparatus. The preferred embodiments expressly extend to any size and dimension for the block and block forming apparatus. In the most preferred application, the block will have a height of 3.0 feet (91 cm), a width of 8.0 feet (244 cm), and a depth of 32 inches (81.3 cm). Blocks with a height of 2.0 feet (61 cm) would also be useful. Blocks that are half the normal width, or 4.0 feet (122 cm) would also be useful in constructing walls with a tighter curvature than is possible with a full-sized block. Note also that the dimensions of the block may be scaled to accommodate different load-bearing requirements. Thus, if a bridge that must bear a freight train needed to be supported by the block of the present invention, its dimensions could be scaled up to provide for larger voids, into which rebar and concrete could be placed to provide a very strong wall capable of bearing substantial loads.

[0064] Note that the units herein are expressed in both English and metric units, so this patent application can be prosecuted in foreign jurisdictions that require metric units without changes to the specification. The preferred embodiments are implemented in English units, and any variation between the stated English units and their metric equivalents is due to rounding errors, with the English units being the more correct measurement of the two.

[0065] While the invention has been particularly shown and described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention. For example, a block may be made in a variety of different sizes, as discussed above. In addition, the size, number and geometries of the block surfaces and voids in the block may vary from that disclosed herein. Furthermore, while the block herein is described as being used for retaining walls, it is equally within the scope of the preferred embodiments to use the building block for other purposes, such as building construction. In addition, while the front, back and side portions of the block forming apparatus are shown to be pivotally coupled to the bottom portion, it is equally within the scope of the preferred embodiments to have these as separate pieces that are coupled to the bottom portion using any suitable fastening technique. 

1. A block comprising: a front surface; first and second side surfaces coupled to the front surface; a top surface coupled to the front surface and to the first and second side surfaces; a bottom surface coupled to the front surface and to the first and second side surfaces, the bottom surface including at least one retaining knob that aligns the bottom surface of the block to the top surface of a previously-placed block; a plurality of voids extending from the top surface to the bottom surface; and a sloped back surface coupled to the first and second side surfaces, to the top surface, and to the bottom surface, the back surface sloping from the top surface to the bottom surface.
 2. The block of claim 1 further comprising: at least one lifting device embedded in the block and partially exposed at the top surface of the block that allows lifting of the block.
 3. The block of claim 1 wherein the block comprises a mixture of sand, gravel, water, and cement in a mix rated at approximately 3000 pounds per square inch (209 kilograms per square centimeter).
 4. The block of claim 1 wherein the at least one retaining knob extends downward and is located behind and adjacent to the top surface of the previously-placed block when the block is stacked atop the previously-placed block.
 5. The block of claim 1 wherein the slope of the back surface is in the range of 5 to 25 degrees.
 6. The block of claim 5 wherein the slope of the back surface is approximately 15 degrees.
 7. A block comprising: a front surface; first and second side surfaces coupled to the front surface; a top surface coupled to the front surface and to the first and second side surfaces; a bottom surface coupled to the front surface and to the first and second side surfaces, the bottom surface including a plurality of retaining knobs that align the bottom surface of the block to the top surface of a previously-placed block, the retaining knobs extending downward from the bottom surface and located behind and adjacent to the top surface of the previously-placed block when the block is stacked atop the previously-placed block; a plurality of voids extending from the top surface to the bottom surface; a sloped back surface coupled to the first and second side surfaces, to the top surface, and to the bottom surface, the back surface sloping from the top surface to the bottom surface at an angle of approximately 15 degrees; at least one lifting device embedded in the block and partially exposed at the top surface of the block that allows lifting of the block; wherein the block comprises a mixture of sand, gravel, water and cement in a mix rated at approximately 3000 pounds per square inch (209 kilograms per square centimeter).
 8. A block forming apparatus for forming a block, the block forming apparatus comprising: a bottom portion having a length and a width; front and back portions along the length of the bottom portion and coupled to the bottom portion; two side portions along the width of the bottom portion and coupled to the bottom portion; the bottom portion, front and back portions, and side portions forming sides of a substantially open box structure; at least one of the front and back portions and the side portions including a plurality of form pockets defined by a metal frame, each form pocket receiving a form liner that defines a textured surface of the block.
 9. The block forming apparatus of claim 8 wherein the front portion, back portion, and two side portions are pivotally coupled to the bottom portion.
 10. The block forming apparatus of claim 8 further comprising a plurality of void forms attached to the bottom portion that create a plurality of voids in the block.
 11. A block forming apparatus for forming a block, the block forming apparatus comprising: a bottom portion having a length and a width; front and back portions along the length of the bottom portion and coupled to the bottom portion; two side portions along the width of the bottom portion and coupled to the bottom portion; the bottom portion, front and back portions, and side portions forming sides of a substantially open box structure; at least one of the front and back portions and the side portions including a plurality of form liners that defines a textured surface of the block.
 12. The block forming apparatus of claim 11 wherein the front portion, back portion, and two side portions are pivotally coupled to the bottom portion.
 13. The block forming apparatus of claim 11 further comprising a plurality of void forms attached to the bottom portion that create a plurality of voids in the block.
 14. A method for manufacturing a block comprising the steps of: (A) preparing a form comprising a bottom portion having a length and a width, front and back portions along the length of the bottom portion and coupled to the bottom portion, and two side portions along the width of the bottom portion and coupled to the bottom portion, the bottom portion, front and back portions, and side portions forming sides of a substantially open box structure, at least one of the front and back portions and the side portions including a plurality of form pockets defined by a metal frame, each form pocket receiving a form liner that defines a textured surface of the block; (B) pouring a layer of block mix within the open box structure of the form; (C) vibrating the block mix; (D) if the form is not full, adding rebar and repeating steps (B) and (C); (E) if the form is full, leveling the block mix to a desired height; (F) allowing the block to cure; (G) removing the front and back portions and the two side portions from the cured block; and (H) removing the cured block from the bottom portion.
 15. The method of claim 14 wherein the form liner is a polyurethane form liner.
 16. A method for manufacturing a block comprising the steps of: (A) preparing a form comprising a bottom portion having a length and a width, front and back portions along the length of the bottom portion and coupled to the bottom portion, and two side portions along the width of the bottom portion and coupled to the bottom portion, the bottom portion, front and back portions, and side portions forming sides of a substantially open box structure, at least one of the front and back portions and the side portions including a plurality of form liners that defines a textured surface of the block; (B) pouring a layer of block mix within the open box structure of the form; (C) vibrating the block mix; (D) if the form is not full, adding rebar and repeating steps (B) and (C); (E) if the form is full, leveling the block mix to a desired height; (F) allowing the block to cure; (G) removing the front and back portions and the two side portions from the cured block; and (H) removing the cured block from the bottom portion.
 17. The method of claim 16 wherein the form liner is a polyurethane form liner.
 18. A method for building a block wall comprising the steps of: (A) laying a base course of blocks, each block in the base course comprising: a front surface; first and second side surfaces coupled to the front surface; a top surface coupled to the front surface and to the first and second side surfaces; a bottom surface coupled to the front surface and to the first and second side surfaces; a plurality of voids extending from the top surface to the bottom surface; and a sloped back surface coupled to the first and second side surfaces, to the top surface, and to the bottom surface, the back surface sloping from the top surface to the bottom surface; (B) laying subsequent courses of blocks, each block in each subsequent course comprising: a front surface; first and second side surfaces coupled to the front surface; a top surface coupled to the front surface and to the first and second side surfaces; a bottom surface coupled to the front surface and to the first and second side surfaces, the bottom surface including at least one retaining knob that aligns the bottom surface of the block to the top surface of a previously-placed block; a plurality of voids extending from the top surface to the bottom surface; and a sloped back surface coupled to the first and second side surfaces, to the top surface, and to the bottom surface, the back surface sloping from the top surface to the bottom surface; wherein each block is placed in each subsequent course by positioning the at least one retaining knob adjacent to and behind the top surface of the previously-placed block.
 19. The method of claim 16 further comprising the step of filling the plurality of voids with a filler material.
 20. A method for doing business comprising the steps of: manufacturing the block forming apparatus of claim 8; and selling or leasing the block forming apparatus for on-site block construction.
 21. A method for doing business comprising the steps of: manufacturing the block forming apparatus of claim 11; and selling or leasing the block forming apparatus for on-site block construction.
 22. A method for doing business comprising the steps of: purchasing the block forming apparatus of claim 8; and selling or leasing the block forming apparatus for on-site block construction.
 23. A method for doing business comprising the steps of: purchasing the block forming apparatus of claim 11; and selling or leasing the block forming apparatus for on-site block construction.
 24. A method for doing business comprising the steps of: purchasing the block forming apparatus of claim 8; transporting the block forming apparatus to a job site; and using the block forming apparatus to fabricate a plurality of blocks on the job site.
 25. A method for doing business comprising the steps of: purchasing the block forming apparatus of claim 11; transporting the block forming apparatus to a job site; and using the block forming apparatus to fabricate a plurality of blocks on the job site. 